WASHINGTON — Even as millions of baby boomers approach retirement, the Social Security Administration has been closing dozens of field offices, forcing more and more seniors to seek help online instead of in person, according to a congressional report being released today. The agency blames budget constraints. As a result, seniors seeking information and help from the agency are facing increasingly long waits, in person and on the phone, the report said. Social Security has closed 64 field offices since 2010, the largest number of closures in a five-year period in the report. In addition, the agency has closed 533 temporary mobile offices that often serve remote areas. Hours have been reduced in the 1,245 field offices that are still open, the report said. “Seniors are not being served well when you arbitrarily close offices and reduce access to services,” said Sen. Bill Nelson, D-Fla., chairman of the Aging Committee. “The closure process is neither fair nor transparent and needs to change.” The committee is holding a hearing on the report this afternoon. By The Associated Press